Robotic Compliant Grinding for Complex Blisk with an Intelligent End-Effector

Abstract

This paper presents a novel robotic blisk grinding method in which a home-designed intelligent end-effector is implemented for active contact force control. The feed direction of the intelligent end-effector is arranged to be the same as the normal direction of the blade surface at the working point. A gravity compensation algorithm is developed to compensate the gravity effect on the contact force measurement. The orientation change of the intelligent end effector is measured with the embedded gyroscope for gravity compensation. A PID controller is implemented for contact force control. The motion control system of the positioning stage receives the control command from the force controller, and adjusts the motor velocity to keep the contact force stay constant. The experimental results show that, compared to the case without force control, the surface roughness and machining consistency are greatly improved with active contact force control. The surface roughness is less than 0.4 μm, the steady state error of the controlled force is about 0.3 N, and the force fluctuation is within 1 N.